two questions you need to ask yourself:

1. did google kill the project for a lack of potential or did it just not fit into their larger picture?

2. are you bringing something to life (i.e. killer feature) that the other project didn't have?

just so you know sometimes a project can be too ahead of its time. sometimes someone can do a very similar a few years later and have a real hit: a good example would be that founder of zynga first did a social networking site like facebook (tribe.net) which failed: http://en.wikipedia.org/wiki/Mark_Pincus#Career